JP2012182362A - Electronic component and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a sealing layer from intruding into a function part and form a space where the function part operates without increasing the size of an electronic component in the electronic component where a function element having the function part is mounted on a wiring board and a sealing layer is provided for protecting at least a joining part between the wiring board and the function element.SOLUTION: An electronic component is formed so that a water-repellent layer is formed at a region facing a function part of a function element on a main surface of a wiring board. The structure inhibits a component resin from flowing into a space between a main surface of the wiring board and a function part of the function element when a sealing resin is formed and forms a space for operating the function part therebetween.

Description

  The present invention relates to an electronic component in which a functional element having a functional part is mounted on a wiring board, and at least a sealing layer for protecting a joint part between the wiring board and the functional element is provided, and its manufacture Regarding the method.

  So-called MEMS (Micro Electro Mechanical Systems) functional elements such as inkjet printer heads, acceleration sensors, pressure sensors, gyroscopes, and surface acoustic wave filter devices are used in order to electrically control them. Flip-chip connection is made on the wiring substrate on which a conductive layer such as a conductive pad is formed via a conductive bump so as to be electrically connected to the conductive layer, and the functional element and the wiring substrate are integrated. Configured as a form of electronic components.

  At this time, a sealing layer made of, for example, a thermosetting resin is formed on the electronic component mainly in order to protect the flip chip bonding portion and further to protect the functional portion of the functional element. However, when the sealing layer reaches the functional part of the functional element, it becomes impossible to secure a space necessary for the functional part to operate. From such a point of view, various attempts have been made to ensure a space necessary for the function part to operate without the sealing layer reaching the function part of the functional element.

  For example, in Patent Document 1, when a surface acoustic wave filter device is mounted by flip chip bonding so that a functional unit is opposed to the main surface of the substrate on the substrate, the substrate and the surface acoustic wave filter device are electrically connected. In order to prevent the sealing layer from reaching the functional part of the surface acoustic wave filter device by the dam material provided outside the conductive bump to be mechanically connected, and to drive the functional part The necessary space is secured.

  However, in this method, since an additional member such as a dam material is separately provided, there is a problem that the size of the electronic component is increased and the application is limited.

JP2003-142523

  The present invention relates to an electronic component in which a functional element having a functional part is mounted on a wiring board and at least a sealing layer for protecting a joint part between the wiring board and the functional element is provided. It is an object of the present invention to form a space in which a functional portion of a layer can be prevented from entering and the functional portion can operate without increasing the size of an electronic component.

In order to achieve the above object, the present invention provides:
A wiring board having a conductive layer formed on at least the main surface;
The functional part is opposed to the main surface of the wiring board, and the conductive layer of the wiring board is connected to the main surface of the wiring board via a conductive member provided outside the functional part. A functional element mounted so as to be electrically connected to the region;
On the main surface of the wiring board, comprising a water repellent layer formed in a region opposite to the functional part of the functional element,
The present invention relates to an electronic component characterized in that a gap is formed between the main surface of the wiring board and the functional part.

The present invention also provides:
A wiring board in which a conductive layer is formed on at least the main surface, and the functional part are opposed to the main surface of the wiring board, and are provided outside the functional part on the main surface of the wiring board. The functional element mounted so as to be electrically connected to the connection region of the conductive layer of the wiring board via the conductive member, and at least a junction between the wiring board and the functional element is protected. A method for manufacturing an electronic component comprising: a sealing layer for forming a water repellent layer formed in a region opposite to the functional portion of the functional element on the main surface of the wiring board;
Before the sealing step with the sealing layer, a water-repellent layer forming step is provided for forming the water-repellent layer on the main surface of the wiring board at a position facing the functional portion of the functional element. The present invention relates to a method for manufacturing an electronic component.

  According to the present invention, a wiring board in which a conductive layer is formed on at least the main surface, and the functional part are opposed to the main surface of the wiring board, and are provided outside the functional part on the main surface of the wiring board. A functional element mounted so as to be electrically connected to the connection region of the conductive layer of the wiring board through the conductive member formed on the main surface of the wiring board, and relative to the functional part of the functional element. In an electronic component having a water repellent layer formed in a facing area, the area facing the functional portion of the functional element on the main surface of the wiring board before the sealing step for forming the sealing layer A water repellent layer is formed on the surface.

  Since the sealing layer is generally composed of a resin, in this case, even when the resin constituting the sealing layer flows between the main surface of the wiring board and the functional part of the functional element, Since the water-repellent layer is present on the main surface of the wiring board facing the portion, the resin cannot be repelled by the water-repellent layer and remain on the layer.

  Accordingly, since the resin constituting the sealing layer can be prevented from flowing between the main surface of the wiring board and the functional part of the functional element, a gap can be formed between them, and sealing can be performed. It becomes possible to suppress the malfunction of the functional part due to the stop layer.

  In addition, in this invention, since it is not necessary to provide additional members, such as a dam material, the problem that the size of an electronic component will enlarge and a use will be limited can also be avoided.

  As described above, according to the present invention, an electronic component in which a functional element having a functional part is mounted on a wiring board and at least a sealing layer for protecting a joint part between the wiring board and the functional element is provided. Therefore, it is possible to prevent the sealing layer from entering the functional part and to form a space in which the functional part can operate without increasing the size of the electronic component.

It is sectional drawing which shows schematic structure of the electronic component in embodiment. It is a perspective view which expands and shows the functional element of the electronic component shown in FIG. It is a figure for demonstrating the operation state of the functional element shown in FIG. Similarly, it is a figure for demonstrating the operation state of the functional element shown in FIG. It is sectional drawing for demonstrating schematically the manufacturing method of the electronic component of embodiment. Similarly, it is sectional drawing for demonstrating schematically the manufacturing method of the electronic component of embodiment.

  Hereinafter, specific features of the present invention will be described based on embodiments for carrying out the invention.

  1 is a cross-sectional view showing a schematic configuration of an electronic component in the present embodiment, FIG. 2 is an enlarged perspective view showing a functional element of the electronic component shown in FIG. 1, and FIGS. FIG. 3 is a diagram for explaining an operation state of the functional element shown in FIG. 2. 5 and 6 are cross-sectional views for schematically explaining the method for manufacturing an electronic component of the present embodiment.

  In the present embodiment, the case of an acceleration sensor as the functional element is described.

  As shown in FIG. 1, the electronic component 10 according to the present embodiment includes a wiring board 11 in which a conductive layer (not shown) is formed on the main surface 11A, and an outside of the functional unit 13A on the main surface 11A of the wiring board 11. An acceleration sensor (function) is electrically and mechanically connected to a metal pad (conductive layer) (not shown) formed on the main surface 11A of the wiring board 11 through a conductive bump 15 provided on the side. 13) is mounted. The acceleration sensor 13 is mounted such that the functional portion 13A and the main surface 11A of the wiring board 11 face each other.

  The conductive bump 15 can be composed of, for example, a gold bump or solder.

  A water repellent layer 12 is formed on the main surface 11 </ b> A of the wiring board 11 in a region facing the functional portion 13 </ b> A of the acceleration sensor 13.

  Further, a sealing layer 14 for protecting the joint portion is formed around the joint portion between the wiring board 11 and the acceleration sensor 13, that is, around the conductive bump 15.

  In the present embodiment, as is clear from FIG. 1, the water repellent layer 12 is formed on the main surface 11 </ b> A of the wiring substrate 11 in a region facing the functional portion 13 </ b> A of the acceleration sensor 13.

  Since the sealing layer 14 is generally made of resin, in this case, the resin constituting the sealing layer 14 flows between the main surface 11A of the wiring board 11 and the functional portion 13A of the acceleration sensor 13. However, since the water repellent layer 12 exists on the main surface 11A of the wiring substrate 11 facing the functional portion 13A, the resin is repelled by the water repellent layer 12 and cannot remain on the layer.

  Therefore, since it can suppress that resin which comprises the sealing layer 14 flows in between 11 A of main surfaces of the wiring board 11, and the functional part 13A of the acceleration sensor 13, the space | gap S is formed among these. Therefore, it is possible to suppress the malfunction of the functional unit 13A due to the sealing layer 14.

  In addition, in this embodiment, since it is not necessary to separately provide additional members, such as a dam material, the problem that the size of an electronic component will enlarge and a use will be limited can also be avoided.

  The water repellent layer 12 can be composed of, for example, a fluorine-based coating agent and a silicone-based coating agent. These materials have been practically used as a water repellent for a long time, have a proven track record, and are easily available. Therefore, the water repellent layer 22 having high water repellency can be formed at low cost. As a forming method, a printing method using a photolithography or a metal mask, a spray method, or the like can be used according to the viscosity of the coating agent.

  Moreover, the thickness of the water repellent layer 12 can be 5 micrometers-20 micrometers, for example. If the thickness is less than 5 μm, the water repellency may not be sufficiently exhibited. If the thickness exceeds 20 μm, it may no longer contribute to the improvement of the water repellency and only the material loss may increase.

  Next, the acceleration sensor 13 which is a functional element in the present embodiment will be briefly described with reference to FIGS.

  As shown in FIG. 2, the acceleration sensor 13 includes a frame portion 131 and two beams that extend from a substantially central portion of each side of the frame portion 131 to a substantially central portion of opposite sides and orthogonal to each other. And a beam portion 132. In addition, a plane portion 133 is formed at a portion of the beam portion 132 where the two beams intersect, and the four weights 134-1 to 134-1 are arranged on the plane portion 133 so that the plane portion 133 is located at the approximate center. 134-4 is attached.

  In the acceleration sensor 13, the frame part 131, the beam part 132, the plane part 133, and the weights 134-1 to 134-4 constitute a functional part 13A.

  The acceleration sensor 13, that is, the frame part 131, the beam part 132, the flat part 133, and the weights 134-1 to 134-4 are made of a semiconductor such as silicon. A piezo element (not shown) is provided on the beam portion 132.

  When no acceleration is applied to the acceleration sensor 13, none of the weights 134-1 to 134-4 vibrate as shown in FIG. On the other hand, when acceleration is applied to the acceleration sensor 13, the weights 134-1 to 134-4 vibrate as shown in FIG. The non-piezoelectric element converts the electric signal into an electric signal and transmits it to an external circuit or the like, and the acceleration can be detected by analyzing the transmitted electric signal.

  Note that the vibrations of the weights 134-1 to 134-4 are not limited to the plane, but also occur in the direction perpendicular to the paper surface. Therefore, the distortion of the beam portion 132 caused by the vibration is also limited to the plane. However, it also occurs in a direction perpendicular to the paper surface as described above.

  Next, with reference to FIGS. 5 and 6, a method for manufacturing the electronic component 10 of the present embodiment will be schematically described.

  First, as shown in FIG. 5, the water repellent layer 12 is formed on the main surface 11 </ b> A of the wiring substrate 11 in a region facing the functional portion 13 </ b> A of the acceleration sensor 13 to be formed later.

  Next, as shown in FIG. 6, the acceleration sensor 13 is pressed under heat against the wiring board 11 through the conductive bumps 15, so that the electrical sensor and the metal pad (conductive layer) (not shown) of the wiring board 11 are electrically and Connect mechanically.

  Thereafter, a resin is applied on the protective layer 12 and in the vicinity of the conductive bumps 15 to form the sealing layer 14. As described above, when the sealing layer 14 is formed, even when the constituent resin flows between the main surface 11A of the wiring substrate 11 and the functional portion 13A of the acceleration sensor 13, the functional portion Since the water repellent layer 12 exists on the main surface 11A of the wiring substrate 11 facing the 13A, the resin is repelled by the water repellent layer 12 and cannot remain on the layer.

  Therefore, since it can suppress that resin which comprises the sealing layer 14 flows in between 11 A of main surfaces of the wiring board 11, and the functional part 13A of the acceleration sensor 13, the space | gap S is formed among these. Therefore, it is possible to suppress the malfunction of the functional unit 13A due to the sealing layer 14.

  The present invention has been described in detail based on the above specific examples. However, the present invention is not limited to the above specific examples, and various modifications and changes can be made without departing from the scope of the present invention.

  For example, in the above specific example, the case of the acceleration sensor as the functional element has been described. However, a gap can be formed between the main surface of the wiring board and the functional part of the functional element, and the functional part by the sealing layer. Any kind of functional element can be used as long as the operation failure can be suppressed, and a so-called MEMS such as a gyroscope and a surface acoustic wave filter device can be used.

10, 20 Electronic component 11 Wiring board 12 Water repellent layer 13 Acceleration sensor (functional element)
14 Sealing layer 15 Conductive bump

Claims (4)

A wiring board having a conductive layer formed on at least the main surface;
The functional part is opposed to the main surface of the wiring board, and the conductive layer of the wiring board is connected to the main surface of the wiring board via a conductive member provided outside the functional part. A functional element mounted so as to be electrically connected to the region;
On the main surface of the wiring board, comprising a water repellent layer formed in a region opposite to the functional part of the functional element,
An electronic component, wherein a gap is formed between the main surface of the wiring board and the functional part.   The electronic component according to claim 1, further comprising: a sealing layer for protecting a joint portion between the wiring board and the functional element.   The electronic component according to claim 1, wherein the water repellent layer comprises at least one of a fluorine-based coating agent and a silicone-based coating agent. A wiring board in which a conductive layer is formed on at least the main surface, and the functional part are opposed to the main surface of the wiring board, and are provided outside the functional part on the main surface of the wiring board. The functional element mounted so as to be electrically connected to the connection region of the conductive layer of the wiring board via the conductive member, and at least a junction between the wiring board and the functional element is protected. A method for manufacturing an electronic component comprising: a sealing layer for forming a water repellent layer formed in a region opposite to the functional portion of the functional element on the main surface of the wiring board;
Before the sealing step with the sealing layer, a water-repellent layer forming step is provided for forming the water-repellent layer on the main surface of the wiring board at a position facing the functional portion of the functional element. A method of manufacturing an electronic component, characterized in that

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